This invention relates to coaxial cable connectors and in particular to such a connector wherein the coaxial cable exits from the body of the connector at an angle, thereby to increase the accessibility of each connector and to decrease the protrusion depth associated with groups of such connectors.
Coaxial assemblies for telecommunication applications, such as DS-3 include many forms: straight, right angle, 735A cable, RG 179 single shield, RG 179 double shield, positive latch SMB and conventional SMB (wherein xe2x80x9cSMBxe2x80x9d stands for Sub-Miniature-type B). SMB connectors were developed to provide a quick connect/disconnect interface with a push on/pull off capability. SMB connectors conform to the requirements of a military specification MIL-C-39012 and the interface is in compliance with a military specification MIL-STD-348. Normally a female SMB connector (e.g., a SMB plug) plugs onto a male SMB connector (e.g., a SMB jack). SMB connectors may be used to couple two networking equipment using coaxial copper cables. In one application, SMB plugs at the ends of coaxial cables are connected to SMB jacks on a printed circuit board (PCB) of a universal access platform or other networking equipment, at a central office of a service provider or a remote box at a customer site. Such a PCB includes rows and columns of SMB jacks packed closely together to reduce space usage. Typically, the coaxial cables are attached to the plug either perpendicularly or coaxially with the axis of the plug. However, a perpendicular attachment limits the density of plugs which be attached to a PCB and thus requires a larger area than desired for a given number of plugs. The coaxial attachment results in coaxial cables protruding into an aisleway where the cables might be bumped and thus dislodged or broken.
The prior art includes what is known as a Bayonet-Neill-Concelman coupling mechanism wherein a rotatable collar is inserted over a male fitting and rotated approximately a quarter turn to lock protrusions on the male fitting into angled slots on the rotatable collar. The coaxial cable exits from the body of the structure supporting the rotatable collar at an angle, such as 45xc2x0. However, this structure is bulky and large so as to be able to be turned by a person""s fingers, and thus this structure is capable of being used only in low density applications.
In accordance with some embodiments of the invention, a SMB plug has two portions that are angled relative to one another, specifically a main body and a wire exit extending approximately 45 degrees from the main body. Presence of such an angle allows the pitch of a two dimensional array of angled SMB plugs to be smaller than in the prior art, resulting in an increased density and increased reliability than the industry currently offers. The angled structure of the SMB plugs of the type described herein also allows easy management (mounting and dismounting) independent of one another. The main body is tubular and has a diameter that is approximately 89 percent of a pitch between (i.e. the distance between the centerlines of) two SMB plugs mounted adjacent to each other (hereafter xe2x80x9cadjacent SMB plugsxe2x80x9d) in one specific embodiment. The wire exit is also tubular and has a diameter that is approximately 59 percent of the pitch between two adjacent SMB plugs in this particular embodiment. Such dimensional relations apply only to a 45xc2x0 angle plug and can be different in other embodiments.
The dimensions of the angled SMB plug are selected to create sufficient clearance between adjacent angled SMB plugs in a two dimensional array to allow each angled SMB plug to rotate to the right or the left without interfering with adjacent angled SMB plugs in the same column. The angle between the coaxial cable exiting from the plug and the centerline of the plug reduces the protrusion depth of the coaxial cables connected to the plug compared to cables coaxially aligned with the plugs and thus reduces the possibility of damage or inadvertent disconnecting or breaking of a plug. Thus, cables of all but one SMB plug in a group of SMB plugs in a two dimensional array can be rotated away (in different directions), to make room for a person""s hand (or a tool) to hold and dismount the unrotated SMB plug. Thus any SMB plug can be mounted or dismounted without affecting any other SMN plug. In one embodiment, cables exit at 45xc2x0 from the plugs thereby reducing coaxial cable protrusion by approximately 50% compared to cables coaxially aligned with the plugs.